One-Minute Mentor: Heat Treating and Properties of Ductile Iron
December 5, 2018
Source:
The basic structural differences between the ferritic and austenitic classes are shown in the graph. It shows a continuous cooling transformation (CCT) diagram and cooling curves for furnace cooling, air cooling, and quenching.
It can be seen that slow furnace cooling results in a ferritic matrix (the desired product of annealing), whereas the cooling curve for air cooling, or normalizing, results in a pearlitic matrix, and quenching produces a matrix microstructure consisting mostly of martensite with some retained austenite.
Tempering softens the normalized and quenched conditions, resulting in microstructures consisting of the matrix ferrite with small particles of iron carbide (or secondary graphite). Actual annealing cycles usually involve more than just furnace cooling, depending on alloy content and prior structure.
Volume 4D, Heat Treating of Irons and Steels -> Heat Treatiment of Cast Irons -> -> Heat Treating and Properties of Ductile Iron -> General Characteristics
The basic structural differences between the ferritic and austenitic classes are shown in the continuous cooling transformation (CCT) diagram and cooling curves for furnace cooling, air cooling, and quenching.
Continue reading
Steel Dynamics to invest $1.6 billion in new electric-arc furnace flat roll steel mill
November 28, 2018
Source:
Steel Dynamics Inc., Fort Wayne, Ind., announces that its Board of Directors has authorized the company to construct a new state-of-the-art, electric-arc-furnace (EAF) flat roll steel mill with annual production capacity of approximately 3.0 million tons, including the capability to produce the latest generation of Advanced High Strength Steel products.
The project will include value-added finishing lines, including a galvanizing line with an annual capacity of 450,000 tons, and a paint line with an annual coating capacity of 250,000 tons. The product offering is anticipated to include various flat roll steel products, including hot roll, cold roll, galvanized, Galvalume and painted steel, primarily serving the energy, automotive, construction, and appliance sectors. The current estimated investment is $1.7 billion to $1.8 billion, with anticipated direct job creation of approximately 600 well-paying positions, and numerous opportunities for indirect job growth from other support service providers.
The company currently expects to locate the facility in the southwestern United States, to cost effectively serve not only the southern United States, but also the underserved Mexican flat roll steel market. Determination of the final site location is subject to state and local government infrastructure and incentive support. Upon final site selection and the receipt of required environmental and operating permits, the company would expect to begin construction in 2020, followed by the commencement of operations in the second half of 2021.
"We plan to utilize new technologies that will further reduce the gap between existing EAF and integrated steel mill production capabilities,†says Mark. D. Millett, President and Chief Executive Officer. “We are excited to announce this investment, which is a culmination of our intentional focus to cost effectively further serve the customers in this growing flat roll steel consuming region, while increasing our steelmaking capacity and value-added product capability.â€
www.steeldynamics.com
Steel Dynamics Inc., Fort Wayne, Ind., announces that its Board of Directors has authorized the company to construct a new state-of-the-art, electric-arc-furnace (EAF) flat roll steel mill with annual production capacity of approximately 3.0 million tons, including the capability to produce the latest generation of Advanced High Strength Steel products.
Continue reading
Sandvik installs Renishaw laser 3D printers and collaborates on process development
Source:
Sandvik Additive Manufacturing, Sweden, announces that it has installed several new Renishaw RenAM 500Q quad laser printing machines, and is also initiating further collaboration with Renishaw in areas such as materials development, AM process technologies, and post-processing.
This print capacity expansion follows a recently announced investment of $22 million in a new plant for the manufacturing of titanium and nickel powders for additive manufacturing. These powders will complement Sandvik’s existing Osprey powder offering to include virtually all alloy groups of relevance today.
The new multi-laser RenAM 500Q systems complement Sandvik’s existing AM machines, which include printers from EOS, Concept Laser, Arcam, and ExOne. Collectively, the machines now cover a very wide range of printing technologies for different materials and applications.
When it comes to additive manufacturing, the optimal balance of weight, strength, hardness, thermal characteristics, flexibility, geometric complexity, surface finish, and other characteristics varies from one application to the next. Therefore, Sandvik works across the entire value chain, from component selection, AM-design and modelling, through material choice/development and optimal printing process, to post-processing, testing, and quality assurance.
With its Osprey range of metal powders, Sandvik has the in-house capability to produce the market’s broadest portfolio of alloys, coupled with the metallurgical expertise to customize the best material for every application.
“We work closely with our customers to tailor alloys in line with their exact requirements, even for small batch print runs,†says Annika Roos, Head of the Powder Division in Sandvik. “Not only do we match the alloy to the purpose, but also we can optimize the particle size for the chosen printing process."
www.additive.sandvik/se
Sandvik Additive Manufacturing, Sweden, announces that it has installed several new Renishaw RenAM 500Q quad laser printing machines, and is also initiating further collaboration with Renishaw in areas such as materials development, AM process technologies, and post-processing.
Continue reading
Women in Engineering Profile: Virginia Osterman
November 26, 2018
Source:
This profile series introduces leading materials scientists from around the world who happen to be females. Here we speak with Virginia M. Osterman, senior scientist at Solar Atmospheres Inc. in Souderton, Pa.
What does your typical workday look like? My role at Solar Atmospheres is to understand the chemistry underpinning the processes we run. I work closely with metallurgists, process engineers, and our furnace operators to progress projects from the idea stage to fully developed procedures suitable for large-scale production. This requires a thorough understanding of the physical and chemical properties of the materials involved. In addition to my role at Solar, I teach a course in vacuum heat treating for ASM International.
What is your engineering background? My background is actually in chemistry. I received my B.S. in chemistry from Northeastern University and then earned a Ph.D. in physical organic chemistry at Yale University. My graduate research focused on thermal rearrangements of highly strained organic ring systems. At Yale, I developed an understanding of reaction kinetics and thermodynamics. I also learned to “engineer†equipment to suit my needs. The experience prepared me very well for problem solving in the real world. My academic background also enabled me to jump fields, from organic chemistry to vacuum heat treating. After graduate school, I began my industrial career at DuPont, developing cleaning products based on biodegradable polymers. When the first of our four sons was born, I left full-time employment and began a consulting career. This allowed me to stay at home to raise my children—which was very important to me—but also allowed me to keep in touch with science and maintain a presence in the workforce. When my children were old enough to be self-sufficient, I transitioned to my current role as senior scientist.
What part of your job do you like most? I have always loved problem solving. So I enjoy running lab experiments. This hands-on experience helps me to fully understand how vacuum heat treating works at a practical level and provides a strong sense of accomplishment. I also enjoy being a member of the great team we have at Solar. It takes all of us to work out all the details of the challenges we face.
If a young person approached you for career advice about pursuing engineering, what would you tell them? I am a big fan of co-op and internship programs. I was fortunate to take part in the co-op program at Northeastern in the early 1980s. I worked with Dr. Julie Yang, who ran the analytical laboratory at W.R. Grace. In those days, there were not many female leaders in industry, so Julie was an early role model for me. She was a Ph.D. organic chemist who moved into materials science. I learned from her the importance of being flexible in my career choices. A final, but very important point, is not to fear failure. A career in STEM education is going to be very challenging. There will be failures—probably many—along the way. It is important to recognize that we learn from our failures and they can lead to great success.
Hobbies? Piano, reading, quilting, and baking (chemistry you can eat). Last book read? “The Nightingale†by Kristin Hannah and “The Jazz of Physics†by Stephon Alexander.
Do you know someone who should be featured in an upcoming Women in Engineering profile? Contact Vicki Burt at [email protected].
This profile series introduces leading materials scientists from around the world who happen to be females. Here we speak with Virginia M. Osterman, senior scientist at Solar Atmospheres Inc. in Souderton, Pa.
Continue reading
Buehler to present webinar on issues regarding testing of heat treated ferrous alloys
November 25, 2018
Source:
Buehler Ltd., an ITW company in lake Bluff, Ill., is to present a webinar (Dec. 4 - 6) that will cover a variety of issues commonly encountered in both metallography and hardness testing of ferrous materials, including common problems and how to avoid them. Critical factors for sample preparation include blade selection, mounting selection, cost-effective preparation techniques, image analysis, and hardness testing.
The webinar is aimed at metallurgical technicians, engineers. and others who carry out metallographic preparation of ferrous materials in laboratories or production environments. The Buehler webinar will be conducted by its global material scientists and will be applicable for those testing iron-based metals (steel, stainless steel, iron, iron-based superalloys) and most traditional heat and surface treatment materials (carburizing, nitriding, induction hardening, etc).
According to Dr. Mike Keeble, Buehler US Laboratory Manager, “Many customers have requested information about common problems with iron, steel, and heat treated surfaces. As the economy is ramping up so is their production, and they want to be sure that their metallography techniques are not compromised.
The webinar will also delve into fundamental considerations for a wide variety of steel and stainless materials, coatings, heat and surface treatments. It will include: Efficiency, Quality, Cost Savings, Etching for Microstructure, Accuracy and Reproducibility in Hardness Testing.
http://www.buehler.com
Buehler Ltd., an ITW company in lake Bluff, Ill., is to present a webinar (Dec. 4 – 6) that will cover a variety of issues commonly encountered in both metallography and hardness testing of ferrous materials, including common problems and how to avoid them.
Continue reading
Abstract from MS&T 2018 technical program: Effects of Post-Build Thermal Processing on the Microstructure of Laser Powder-Bed Produced 17-4 PH Stainless Steel
November 24, 2018
Source:
17-4 PH is a martensitic stainless steel of interest for additive manufacturing (AM) applications because of its combination of high strength and corrosion resistance. In the wrought form this steel has a fully martensitic structure that can be strengthened by precipitation of fine Cu-rich FCC precipitates upon aging. When produced via AM, its microstructure depends strongly on the powder feedstock, particularly the gas used during powder atomization, typically argon or nitrogen. Argon-atomized powder costs significantly more than that produced with nitrogen.
However, nitrogen is a strong austenite stabilizer in iron and steel, resulting in an as-built microstructure of AM 17-4 PH that contains up to 90% retained austenite.
Conventional annealing heat treatments reduce the retained austenite to around 10% to 15%, even after cryogenic treatment, resulting in mechanical behavior that differs significantly compared to cast/wrought 17-4 PH.
This work examines alternative post-build processing of nitrogen gas-atomized AM 17-4 PH to minimize or eliminate the retained austenite in the final microstructure, producing a material that more closely resembles its cast/wrought counterpart.
Eric Lass, Carelyn Campbell, Maureen Williams, National Institute of Standards & Technology (NIST)
www.nist.gov
https://www.nist.gov/people/eric-lass
17-4 PH is a martensitic stainless steel of interest for additive manufacturing (AM) applications because of its combination of high strength and corrosion resistance.
Continue reading
Idaho National Lab develops heat treatment to extend life of superalloys in nuclear reactors
Source:
Researchers at Idaho National Laboratory, Idaho Falls, announce that they have developed a heat treatment process that enables superalloys to withstand high heat more than six times longer than an untreated counterpart, extending useful life by thousands of hours in applications such as nuclear reactors.
"We came up with a way to make a superalloy that is much more resistant to heat-related failures. This could be useful in electricity generators and elsewhere," says Subhashish Meher, an INL materials scientist. He was lead author of a new Science Advances paper describing the research.
INL scientists have been studying nickel-base superalloys, which are useful for electricity-generating turbines and high-temperature nuclear reactor components. Previous research had shown that performance can be improved if the material structure of the superalloy repeats in some way from very small sizes to very large, like a box within a box within a box.
This is called a hierarchical microstructure. In a superalloy, it consists of a metallic matrix with precipitates, regions where the composition of the mixture differs from the rest of the metal. Embedded within the precipitates are still finer-scale particles that are the same composition as the matrix outside the precipitates — conceptually like nested boxes.
Dr. Meher and his coauthors found that with the right recipe of heating and cooling, they could make the precipitates two or more times larger than would be the case otherwise, thereby creating the heat-resistant microstructure.
These larger precipitates last longer when subjected to extreme heat. Moreover, computer simulation studies suggest that the superalloy can resist heat-induced failure for 20,000 hours, compared to about 3,000 hours normally.
One application could be electrical generators that last much longer because the superalloy structures would be tougher. What's more, INL scientists may now be able to come up with a procedure that can be applied to other superalloys. So, it may be possible to adjust a superalloy's strength, heat tolerance, or other properties to enhance its use in a particular application.
https://www.inl.gov/article/treated-superalloys-demonstrate-unprecedented-heat-resistance/
Researchers at Idaho National Laboratory, Idaho Falls, announce that they have developed a heat treatment method that enables superalloys to withstand high heat more than six times longer than an untreated counterpart, extending useful life by thousands of hours in applications such as nuclear reactors.
Continue reading
Quintus Technologies system combines HIP with heat treatment at Lake City
November 23, 2018
Source:
Quintus Technologies, Sweden, announces that Lake City Heat Treating, Warsaw, Ind., has installed a Quintus hot isostatic press with uniform rapid cooling, the first to be delivered to the North American market.
“Quintus HIPs are the only systems that can combine traditional hot isostatic pressing with heat treatment in the same cycle,†says Jan Söderström, CEO of Quintus Technologies.
The new press enhances Lake City’s ability to meet demanding customer turnaround requirements by integrating the application of high pressure and heat treatment in a single system. The combined materials densification processes results in parts with improved fatigue and ductile properties to satisfy the critical performance parameters of the aerospace and medical device industries.
The QIH 122 URQ model press is the third Quintus HIP to be included in Lake City’s production portfolio, and the first with controlled cooling rates up to 390°F (200°C) per minute, to be installed in North America.
“Our presses are the only systems that combine traditional hot isostatic pressing with heat treatment in the same cycle, in a process known as high pressure heat treatment,†says Mr. Söderström, “With high-speed quench rates approximating those of vacuum cooling, this innovation increases throughput and lowers costs.â€
The new Quintus HIP has a capacity of 2000 pounds (900 kg) per load, significantly larger than Lake City’s existing systems. Combined with the efficiencies of high pressure heat treatment, the service provider can now offer its aerospace and medical customers shortened lead times while focusing on continued growth in production.
The new HIP will be housed in a recently completed 6000-square-foot addition to its facility. The system features a work zone of 26 inches (660 mm) in diameter and 68.9 inches (1,750 mm) in height; an operating temperature of 2552°F (1400°C); and pressure of 30,000 psi (2,070 bar). In addition to boosting productivity, the system saves time and space, lowers energy consumption, and reduces infrastructure needs.
http://www.quintustechnologies.com
http://www.lakecityheattreating.com
Quintus Technologies, Sweden, announces that Lake City Heat Treating, Warsaw, Ind., has installed a Quintus hot isostatic press with uniform rapid cooling, the first to be delivered to the North American market.
Continue reading
Quintus Technologies system combines HIP with heat treatment at Lake City Heat Treating
Source: ASM International
Quintus Technologies, Sweden, announces that Lake City Heat Treating, Warsaw, Ind., has installed a Quintus hot isostatic press with uniform rapid cooling, the first to be delivered to the North American market.
Continue reading
Oil quench tank is custom-designed for metal stamping dies heated to 1550°F
Source:
L&L Special Furnace Co. Inc., Aston, Pa., has supplied a custom designed and manufactured oil quench tank that was designed to quench metal stamping dies that are heated to 1550°F. The quench tank, which has usable dimensions 12 x 12 x 24 inches, has an oil medium that is agitated by a one-horsepower pump that is directed up under the parts basket. An oil-to-water cooling heat exchanger controls the oil temperature. The system is designed to run one cycle per hour with 35 pounds of parts.
A resting stand is designed with the quench tank to allow the parts to drain after quenching. The oil flows back into the quench tank through an integrated drip tray that is attached to the stand. Ball valves located on the inlet and outlet of the quench tank allow further control of the quench medium.
www.llfurnace.com.
L&L Special Furnace Co. Inc., Aston, Pa., has supplied a custom designed and manufactured oil quench tank that was designed to quench metal stamping dies that are heated to 1550°F.
Continue reading 